Colinus Virginianus Research Articles

Lactobacillus colini sp. nov., isolated from Northern Bobwhite (Colinus virginianus).

Biochemical and molecular studies were performed on five unknown bacterial strains isolated from the intestinal contents of Northern Bobwhites (Colinus virginianus) collected from western Texas, USA. The strains were Gram-stain-positive, catalase-negative, non-spore-forming rods arranged in single cells, pairs or short chains. Colonies on Columbia blood agar are circular, flat, entire, approximately 0.5-1.5 mm in diameter and surrounded with a zone of alpha-haemolysis at after incubation for 48 h at 37 °C. Colonies on MRS agar are umbonate with irregular edge, opaque and approximately 1-1.5 mm in diameter after incubation for 48 h. The 16S rRNA gene sequences of the isolates were identical and the highest sequence similarity (97 %) was found to the type strains of Lactobacillus gasseri, L. johnsonii and L. taiwanensis. The strains were distinguishable from related species of the genus Lactobacilluson the basis of carbohydrate fermentation, enzymatic production and fatty acid profiles. The peptidoglycan type is l-Lys-d-Asp (A4α). The DNA G+C content is 35.6 mol%. Major cellular fatty acids are C14 : 0, C16 : 0 and C18 : 1 ω9c. Based on phenotypic, phylogenetic and chemotaxonomic information, the strains represent a novel species of the genus Lactobacillus for which the name Lactobacillus colini sp. nov. is proposed. The type strain is 111144 L1T (=DSM 101872T=KCTC 21086T).

Effects of fire management on northern bobwhite brood ecology

Northern Bobwhite Colinus virginianus chicks require ample invertebrates for growth and feather development. Early successional or resprouting vegetation provides invertebrates for chicks but may not provide other resources such as roosting and loafing cover that is typically provided by later successional stages. Thus, management for bobwhites provides multiple seral stages in close proximity but the effects of landscape interspersion have not been tested for bobwhite broods. During a 2-year study, we explored the effects of landscape complementation and food availability on growth and survival of bobwhite chicks. We found growth of chicks to be negatively related to home range size which was negatively correlated to the amount of area burned. We also found survival of chicks to be positively related to the amount of burned area (i.e., foraging area) within brood home ranges. To maximize the growth and survival of bobwhite chicks, it would be necessary to increase access to foraging areas while decreasing the size of brood home ranges. Access to foraging areas can be created through frequent prescribed fire at small spatial scales.

A Focused Habitat Approach for Northern Bobwhite Restoration in Kentucky

The Kentucky Department of Fish and Wildlife Resources has measured northern bobwhite (Colinus virginianus) population trends since 1960. During that span, northern bobwhite steadily declined because clean agriculture, fescue-sod, plant succession, and development eroded habitat suitability. Multiple efforts have failed with regard to restoring northern bobwhite numbers. Over 3.5 million northern bobwhite were released by the Department over a three decade period. Habitat efforts on private lands were deployed for over 20 years with mixed results. Support for the habitat restoration efforts waned. In 2008, the Department unveiled a new strategy centered on restoring concentrated habitat in focal areas. From 2008 to 2013, the Department managed habitat and monitored breeding northern bobwhite on 5 focal areas that were distributed throughout the state. Focal areas ranged in size from 1,155 to 16,517 ha. A total of 109 breeding bird survey points were monitored annually with up to three repetitions. Habitat management activity was also tracked. We used distance sampling to model density-dependent and density-independent population growth. Across the study, there was a 0.992 probability that our populations were growing with a mean region-wide, density independent growth rate of 35.7% annually. We were able to grow populations in an array of landscapes that were dominated by agriculture and grasslands. Management actions maintaining ≥10% of the focus areas in early successional habitat consistently supported growing northern bobwhite populations. The unique nature of our focal areas made them poor laboratories for field study, so future multi-state collaboration may be essential to understand the factors driving northern bobwhite growth. A better understanding of northern bobwhite population growth as it relates to landscape, management, weather, and harvest metrics will improve management prescriptions for northern bobwhite habitat on larger landscapes in the future.

Comparative Morphology and Phylogenetic Relatedness Among Bobwhites in Southern U.S. and Mexico

We analyzed the morphology and phylogenetic relatedness of masked bobwhites (Colinus virginianus ridgwayi) and Texas bobwhites (C. v. texanus) to determine if the numerically stable Texas bobwhite might serve as a reasonable research and management model for the endangered masked bobwhite. We compared 26 external and 24 internal morphological features. Texas and masked bobwhites had similar body mass; however, masked bobwhites had smaller head and body dimensions and longer wing and thigh bones (P < 0.01) than Texas bobwhites. Genomic DNA was extracted from heart or muscle tissue of captive masked bobwhites (n = 12) and from northern bobwhites obtained in Florida (n = 3), Tennessee (n = 5), Texas (n = 12), and Oklahoma (n = 3). Bobwhites from South Texas and masked bobwhites appear to form a relatively closely related assemblage, possibly representing a separate lineage from other bobwhite populations. Based on gross similarities between Texas and masked bobwhites in morphology and phylogenetic relatedness, as well as in habitat conditions on the semiarid rangelands they occupy, biological and management information from Texas bobwhites seems applicable to masked bobwhites.

Masked Bobwhite: Status of an Endangered Subspecies

The masked bobwhite (Colinus virginianus ridgwayi), first collected in 1884, soon disappeared and was considered extinct by 1950. Its rediscovery in 1964 precipitated an aggressive effort to restore the masked bobwhite within its range in both the United States and Mexico. The masked bobwhite, despite this effort, has continued to decline with a precipitous decrease in numbers in the last decade. Surveys conducted in 2009 and 2010 resulted in no detections; for all practical purposes the masked bobwhite is now extinct in the wild. Fortunately, a captive population continues to exist and with proper management can produce sufficient masked bobwhite to restore the wild population. The Masked Bobwhite Recovery Program has been developed and is implementing a bi-national recovery strategy with Mexican cooperators that includes: (1) construction of a new captive breeding facility on Buenos Aires National Wildlife Refuge and adoption of new husbandry and rearing protocols; (2) contracting with the San Diego Zoo Conservation Research Center to manage and operate the new facility; (3) construction of a new facility at Africam Safari, Puebla, Mexico; (4) creation of a reintroduction program in Sonora, Mexico; (5) development of a Mexican landowner outreach program; and (6) a habitat improvement and predator management program on Buenos Aires National Wildlife Refuge.

Potential Polygamous Breeding Behavior in Northern Bobwhite

Breeding behavior ofradio-tagged northern bobwhite (Colinus uirginianus) was observed at Fort Bragg Military Reservation (n = 19), North Carolina, in 1985-88, and Tall Timbers Research Station (n = 27), Florida, during 1984-86. We observed apparent polygamous breeding behavior in 95% (18 of 19) of the radio-tagged northern bobwhite at Fort Bragg, and 93% (25 of 27) of the birds at Tall Timbers. We documented 5 cases of double-clutching by radio-tagged females. Twenty-seven percent of Fort Bragg clutches (n = 30), and 20% of Tall Timbers clutches (n = 56) were incubated by radio-tagged males. Northern bobwhite exhibited characteristics of both rapid multiclutch and am bisexual polygamous mating systems. Northern bobwhite are capable of uniparental care, have long breeding seasons, live in an environment with fluctuating resources, suffer high predation pressure during the nesting season, and raise precocial young; all traits that are similar to other bird species which have evolved polygamous mating systems.

Genetic Diversity and Relatedness Within and Among Northern Bobwhite Coveys in South Texas

Although biologists have studied northern bobwhite (Colinus virginianus) genetic diversity and population structure, there is little known about the genetic diversity, structure, and relatedness of their winter coveys. Both flexible mating strategies and the fall shuffle may have implications for inbreeding and genetic diversity in northern bobwhite populations. Our goal was to determine genetic diversity and relatedness for coveys on a private ranch in Jim Hogg County in South Texas. During the 2010–2011 and 2011–2012 hunting seasons, 96 northern bobwhites were sampled from 29 coveys. We analyzed 11 northern bobwhite microsatellite DNA loci, measured genetic structure with an Analysis of Molecular Variance and FST, and determined an inbreeding coefficient (Fi). We determined Queller and Goodnight’s coefficients of relatedness (R) and then used a maximum-likelihood algorithm in COLONY to assign relationships (parent–offspring, full siblings, and half siblings). Most genetic variation (92%) was within coveys. The overall FST was 0.073, indicating moderate genetic structure among coveys. Relationship coefficients ranged from –0.82 to 1.00 but most of the bird pairs were unrelated (R = -0.004 ± 0.002 SE). In 2010–2011, COLONY assigned 130–149 half sibling, 1–4 full sibling, and 0–3 parent-offspring pairs (n = 2,887, 5 trials, probability >0.99). Thirteen coveys (56%) had related individuals (n = 20 pairs). In 2011– 2012, COLONY assigned 5–10 half sibling and 1 full sibling pairs (n = 161). Two coveys (33%) had related individuals (2 pairs). The occurrence of relatives in different coveys suggests that the fall shuffle is effective at mixing families and the high half sibling count among coveys may suggest polygamy. These strategies may help northern bobwhite populations maintain moderate genetic diversity.

Use of Extinguish Plus™ to Reduce Red Imported Fire Ants and Increase Northern Bobwhite Abundance

Populations of northern bobwhite (Colinus virginianus) have been declining throughout Texas since at least the 1970s. The red imported fire ant (RIFA, Solenopsis invicta) was introduced from South America and reached Texas by the 1950s. Previous studies have documented the negative effects of RIFA on northern bobwhite populations through both direct predation and indirect reduction of small invertebrates. In 2013, 2014, and 2015, large areas (1,490 ha in 2013 and 2,380 ha in 2014 and 2015) of the 3,744-ha portion of the Attwater Prairie Chicken National Wildlife Refuge (APCNWR) in Colorado County, Texas, were aerially treated with Extinguish Plus™, a chemical pesticide and reproductive inhibitor that targets ants. Our study took place on APCNWR and our objectives included evaluation of the impacts of RIFA treatment on 1) RIFA abundance, and 2) northern bobwhite nest success and brood survival. We trapped, banded, and radiocollared northern bobwhites in areas treated and not treated with Extinguish Plus from May 2014 through August 2016. We also collected RIFA abundance data using baited Petri dishes on areas treated and nontreated areas during these periods. Treatment reduced RIFA presence on the refuge by 73.4% during 2014 and 2015, but did not reduce RIFA presence during 2016 possibly because of displacement of RIFA colonies due to heavy flooding on the refuge. We detected a difference (χ21 = 11,009, P = 0.0009) in the number of females sighted with and without broods between treated (19.5% F with broods) and nontreated areas (35.7% F with broods). We also found a difference (t12 = 2.51, P = 0.027) in mean number of chicks per brood sighted within treated (4.7) versus nontreated (9.3) areas for 2014 and 2014; but in 2016, we found no difference (t12 = 0.32, P = 0.754) in mean number of chicks per brood sighted within treated (7.7) and nontreated (8.4) areas, which was possibly due to extensive flooding in the nontreated area in April that destroyed most first nests. Our data suggested treatment with Extinguish Plus did not increase northern bobwhite abundance on the APCNWR during the 2014, 2015, and 2016 bobwhite nesting seasons. Our results differ from previous studies, possibly because of time since treatment and differences in environmental factors between treated and nontreated areas such as ecological site, vegetation composition, and predator abundance.

Is Quail Hunting Self-Regulatory? Northern Bobwhite and Scaled Quail Abundance and Quail Hunting in Texas

Wildlife managers often maintain that quail hunting is self-regulatory because they assume hunters spend fewer days hunting, and bag fewer quail per day, when hunting is "poor," while hunting more frequently, and bagging more quail per day, when hunting is "good." For this reason, managers conclude that minor changes in hunting season length and bag limit are inconsequential. We used August quail abundance (1978-1996) and harvest (1981-1983, 1986---1996) data collected by Texas Parks and Wildlife Department biologists to test the "self-regulatory" hypothesis for both northern bobwhites (Colinus virginianus) and scaled quail (Callipepla squamata). First, we tested the hypothesis that quail abundance in August was sufficient to account for the total number of quail bagged by hunters during the subsequent hunting season. We then tested the hypotheses that quail abundance could predict: (1) the number of days people hunted quail; (2) the number of quail bagged per hunter per day; and (3) the number of quail hunters during the subsequent hunting season. Quail abundance in August was correlated with the number of northern bobwhite and scaled quail bagged during the following hunting season (r2 = 0.769 and 0.874, P <0.0005, respectively). Texas hunters typically hunted quail about 2.5 to 3 days annually regardless of quail abundance. Quail abundance in August, however, was correlated with the number of quail bagged per hunter per day and the number of quail hunters during the subsequent hunting season (northern bobwhite: r2 = 0.895 and 0.868, P <0.0005, respectively; scaled quail: r2 = 0.833 and 0.740, P < 0.0005, respectively). These results are consistent with the hypothesis that both northern bobwhite and scaled quail abundance can regulate quail hunting effort and success within the framework of the hunting regulations that have been in effect in Texas since the early l 980's.

Phylogeography of Bobwhites

Bobwhites (Colinus spp.) are a widely distributed genus of New World quails. Four species are recognized with a geographic range spanning the eastern United States to northern South America. The northern bobwhite (C. virginianus) historically occurred throughout much of the eastern United States and eastern Mexico with disjunct populations in Sonora and Cuba. The Yucata ́n bobwhite (C. nigrogularis) occurs in allopatric populations in Nicaragua and Honduras, and on the Yucata ́n Peninsula. The spot-bellied and crested bobwhites (C. leucopogon and C. cristatus) constitute a species complex with the spot-bellied bobwhite distributed from Guatemala to Costa Rica, and the crested bobwhite from Panama to northern Brazil. The 4 species exhibit substantial intraspecific variation, and up to 56 subspecies are recognized among Colinus largely on the basis of geographic distribution and male plumage coloration. However, relationships within and among species have not been studied in detail. We sampled museum study skins and obtained DNA sequences from mitochondrial control region and ND2 genes. We used concatenated sequences of control region and ND2 to investigate relationships among the bobwhite species, and the control region to assess the geographic distribution of genetic variation within each species. Maximum likelihood analysis of bobwhite phylogeny revealed Colinus is composed of two deeply divergent lineages, one clade of northern and Yucata ́n bobwhites and another of spot-bellied and crested bobwhites. The Yucata ́n bobwhite was genetically distinct from the northern bobwhite. The Yucata ́n bobwhite was composed of 2 distinct subclades, one confined to the Yucata ́n Peninsula and another occurring in Nicaragua. The genetic data showed the spot-bellied bobwhite is closely related to the crested bobwhite, but did not reveal clear support for 2 distinct species. The crested bobwhite was composed of 3 distinct lineages: a western clade that occurs in Panama and west of the northern Andes in Venezuela and Colombia, an eastern clade concentrated in Venezuela (east of the Andes), and a clade restricted to northern Brazil. We found 58 control region haplotypes, of which 29 were shared among 2 northern bobwhite subspecies and 5 haplotypes were especially geographically widespread. We found 16 haplotypes in the Yucata ́n bobwhite with 4 restricted to the Yucata ́n Peninsula and shared among the 3 subspecies found there, and 3 other haplotypes restricted to the Nicaraguan subspecies. The spot-bellied bobwhite did not share haplotypes with any of the 3 crested bobwhite subclades. We found little phylogeographic structure within the spot-bellied bobwhite, and 2 of the 5 haplotypes occurred across much of the species’ range and were shared among the 6 subspecies. The crested bobwhite exhibited strong phylogeographic structure and a lack of shared haplotypes among subspecies. The 20 haplotypes of the crested bobwhite were distributed unevenly among its 3 clades: 2 haplotypes in the Brazilian clade, 6 in the eastern clade, and 12 in the western clade. The weak phylogeographic structure and geographically widespread haplotypes of the northern bobwhite suggests large effective population size and gene flow among subspecies. The deep phylogeographic breaks within the Yucata ́n bobwhite and the spot-bellied bobwhite-crested bobwhite complex may be due to changes in the availability of suitable habitat and geological events during the Pleistocene. The lack of geographically distinct groups within the northern bobwhite implies that many subspecies may not provide good management units. Our data support the continued recognition of the Yucata ́n bobwhite as a distinct species. The 2 intraspecific groups identified in the Yucata ́n and the 4 groups within the spot- bellied/crested bobwhite complex may each represent discrete management units. Further assessment of the phylogenetic relationships and the phylogeography of the bobwhite species is warranted to clarify the phylogeny of Colinus.

Northern Bobwhite Home Range Sizes and Movements in South Texas

Northern bobwhites (Colinus virginianus) often have relatively small home ranges (1-km radius); however, occasional long-distance movements also have been recorded, which may help maintain connectivity and genetic diversity within and among populations. We quantified movements of radiocollared northern bobwhites on the King Ranch in South Texas, USA. For each bird we determined core area, home range (fixed kernel), mean movement rate, and maximum distance moved. We compared movements across age, gender, precipitation trends, and plant communities using Mann–Whitney U and Kruskal–Wallis tests. Almost half (44.7%) of the birds moved >400 m (max. distance moved) and 46 (16%) moved >1 km over the course of the study. Males had higher movement rates (juvenile x̄ = 54.9 m, SE = 1.77 m, n = 64; adult x̄ = 56.6 m, SE = 1.95 m, n = 65) than females (juvenile x̄ = 51.26 m, SE = 1.80 m, n = 102; adult x̄ = 48.14 m, SE = 1.49 m, n = 62; χ23,289 = 14.90, P = 0.02). Maximum distance moved was longer in dry years (609.8 ± 136.3 m) compared with normal or moist years (x̄ = 542.8 m, SE = 47.0 m; x̄ = 536.6 m, SE = 28.8 m, respectively, n = 293). Northern bobwhites moved farther in dry years, possibly to find cover and food. A small percentage made relatively long-distance movements (n = 18, 6%, >1.6 km, max. 6.5 km). These rare movements may influence gene flow and genetic structure of northern bobwhite populations in South Texas.

Body Fat Content of Bobwhites in Relation to Food Plantings in Kansas

A wildlife habitat improvement program was initiated on the Fort Riley Military Reservation in 1961 to increase winter food supplies for bobwhite quail (Colinus virginianus). As part of an ongoing evaluation of this program, 164 bobwhite quail were collected during the fall and winter of 1968-72 for fat analysis. Fat content in carcasses of birds collected <600 m from a food plot was compared with fat content of birds collected>900 m from a food plot. During winter months, birds collected near a food plot were significantly (P<0.10 to P<0.05) heavier than birds not having access to a food plot. Fat content of birds close to a food plot was likewise greater (P<0.10 to P<0.01) than fat content in birds not using food plots. Calculations indicate that birds close to food plots have sufficient energy reserves to provide a 79% greater protection against brief periods of food deprivation than birds far from a food plot. Fat energy reserves alone in a quail close to a food plot could provide sufficient energy for 2.0 days of survival whereas quail far from food plots contained fat energy reserves sufficient for only 1.1 days of survival. Reserve energy for animals is stored in the body mainly in the form of fatty acids. The quantity of stored reserve energy (fat) may be critical to the animal's survival during periods of food scarcity or extremely cold weather. Much work has been done on fat content, composition, and regulation in songbirds (8, 9, 10, 11, 12, 15, 16, 23, 24). Only recently has any attention been given to body fat reserves of wild gallinaceous birds under natural conditions. West and Meng (25) reported on the relationship of total fat and fatty acid composition to diet of willow ptarmigan (Lagopus lagopus) in Alaska while Moss and Lough (14) presented similar data for 3 species of grouse in Scotland. Almost no attention has been given to fat reserves of bobwhite quail even though it is known that fat reserves may be essential for bird survival during periods of dietary stress (15, 23 and others). The most recent book on bobwhite quail (22) does not even discuss the importance of maintaining adequate fat reserves in quail for winter survival and spring breeding. In fact, not until only very recently has any attention been focused on basic energetics of bobwhite quail (3). Earlier I included a small amount of body-fat data

Effects of DDT on Steroid Metabolism and Energetics in Bobwhite Quail (Colinus Virginianus)

Female bobwhite quail (Colinus virginianus) fed low levels (5 ppm) of DDT in their diets showed increased enzyme induction in the liver and consequently a significant increase in steroid (progesterone) metabolism (a mean of 54% conversion of progesterone to its more polar metabolite in experimentals compared to a mean of 24.1% conversion in controls). The mean conversion of testosterone to its polar metabolite (25.1%) in experimental males was greater than in the controls (mean 18.1%) but was only significantly greater in certain males. There was a correlation (r = 0.7 P<0.01) between percent body weight of testes and percent conversion of testosterone to its metabolites (the smaller the testes the greater the conversion). A correlation (r = 0.66 P<0.02) was also found between circulating levels of DDE, DDT, and testes size (the higher the pesticide level the smaller the testes). Dietary levels of DDT (10,50,100,150 ppm) affected the energetics (oxygen consumption) of bobwhite quail. All DDT-treated birds had a higher metabolic rate than the controls at all ambient temperatures tested except 30 C. After acclimation to an ambient temperature of 5 C for 10-13 weeks, birds on 100-ppm DDT diets had a significantly (P<0.01) higher metabolic rate than controls. After one week of exposure to -18 C there was a significant (P<0.02) increase in thyroid weight in the birds on 100-ppm diets. Birds on 100-ppm diet exposed to extreme cold for 1 week died of DDT toxicity. Data on tissue residue levels, weight changes, I uptake by the thyroid, and adrenal changes are also presented. The ecological significance of the synergistic effect of DDT and cold stress on the bobwhite quail is discussed.

Habitat Space Used by Northern Bobwhites and Texas Tortoises on South Texas Rangelands

South Texas rangelands are increasingly managed for recreational hunting, particularly northern bobwhite (Colinus virgianus). Effects of habitat management for game species on non-game species are largely unknown. Large private ranches used for recreational hunting could also provide habitat for the threatened Texas tortoise (Gopherus berlandieri). We studied habitat use of Texas tortoises and northern bobwhites on a private ranch in South Texas that undergoes active habitat management. In 2015, tortoises (n = 12) and bobwhite hens (n = 42) were tracked during their active and breeding seasons, respectively, with radio-telemetry. Satellite images were analyzed using ArcGIS 10.3 to delineate habitat through unsupervised classification for relevant habitat categories. Habitats were delineated based on reflectance. Differences in percent habitat composition of observed and random home ranges (100% Minimum Convex Polygon) of tortoises were not significant, but were significant for quail in 3 of 5 habitat categories in only 1 of 2 pastures. These observed quail home ranges included more areas corresponding to light woody cover and moderate herbaceous cover and fewer areas corresponding to sparsely vegetated or bare ground than random home ranges. Tortoise home ranges included more areas with woody brush cover than bobwhite home ranges. Bobwhite home ranges included more areas associated with moderate grass and herbaceous cover than tortoises. This study will continue in 2016 and will include more quail home ranges in areas with tortoises. This research seeks to determine the compatibility of managing for recreational hunting while maintaining landscape characteristics important to Texas tortoises.

Propagation Effectiveness of the Surrogator for Northern Bobwhites in Southern Texas

Attempts to restore populations of northern bobwhites (Colinus virginianus) using pen-raised quail have been documented since the early 1900s. Low restoration success, based on low post-release survival rates and long distance dispersal from release sites, have proven the ineffectiveness of pen-raised quail in restoration of wild populations. The Surrogatort, a recent quail propagation tool using pen-raised quail, has been publicized as a method for increasing success rates in restoration of northern bobwhite populations by producing higher post-release survival and minimal dispersal. We tested the hypothesis that the Surrogatort is an effective means of supplementing populations of northern bobwhites in southern Texas. We raised 1,000 northern bobwhites in 2 Surrogators and conducted 2 trials in 2010 on a 990-ha ranch in Wilson County, Texas. Twenty northern bobwhites from each Surrogator were fitted with radio transmitters 12 hrs before release. We attempted to locate each bird daily for 3 weeks upon release from Surrogators followed by a reduced effort of 3 times per week until 100% mortality. Daily survival rates were low in Trial 1 (Surrogator A 1⁄4 0.87 and Surrogator B 1⁄4 0.96) and Trial 2 (Surrogator A 1⁄4 0.83 and Surrogator B 1⁄4 0.87). Mean distances traveled by post-released birds for Trial 1 were 401 and 1,416 m for Surrogators A and B, respectively. The Surrogator is not an effective means of restoring wild populations of northern bobwhites in southern Texas.

Uncertainty and the Entanglement of Habitat Loss and Fragmentation Effects in the Management of Northern Bobwhite

There is a need to understand the effects of habitat loss and fragmentation on northern bobwhite (Colinus virginianus) and other grassland bird species and relate this to conservation action and delivery, especially in areas of intensive anthropogenic development. Through our research, we investigated the factors contributing to habitat loss and fragmentation in order to prioritize management within the Gulf Coast Prairie Landscape Conservation Cooperative (GCP LCC) region of Texas, USA. For this geographic region, we completed these objectives: analyzed grassland bird habitat loss and fragmentation resulting from oil and gas development, which has become especially rapid in this region beginning in 2008, projected future habitat loss under possible future economic scenarios, modeled the outcomes of potential management alternatives, and identified drivers of habitat loss and fragmentation to direct management action toward minimizing threats to high-risk habitats. Using a modeling approach, we identified suitable bobwhite habitat and prioritized high-risk areas, particularly focusing on the best candidate areas for successful restoration. Briefly, point count data were related to patch- and landscape-level habitat characteristics using a modeling technique that formally estimated the scale of the landscape effect on bobwhite abundance. Thereafter, we identified possible management alternatives with the guidance of the GCP LCC and other stakeholders and modeled the consequences of these alternatives. Using results from this modeling, we produced an extinction risk map for northern bobwhite in this region. Our research adds to the understanding of the relationship between northern bobwhite populations and the expansion of energy extraction and also uses modeling informed by data to support a decision-making framework that incorporates uncertainty about this system to prioritize the conservation of high-risk and high-value areas of bobwhite habitat.

Northern Bobwhite Survival Related to Movement on a Reclaimed Surface Coal Mine

Reclaimed coal mines represent opportunity to provide large tracts of early succession habitat essential to northern bobwhite (Colinus virginianus) populations. However, little research has been conducted to explore the potential of reclaimed mine sites and examine bobwhite ecology on these unique areas. Reclaimed mines in Kentucky were planted to non-native species, such as sericea lespedeza (Lespedeza cuneata) and tall fescue (Festuca arundinacea), which do not provide suitable structure for northern bobwhite brood-rearing and movement. Fallow disking (in blocks and linear firebreaks) and planting food plots are part of current management efforts to improve food availability and habitat structure for broods. We trapped and radiomarked 266 northern bobwhites between April 2010 and September 2011 on Peabody Wildlife Management Area, a 3,330-ha reclaimed coal mine in western Kentucky, USA to investigate the effects of current management practices on movement and survival. We calculated seasonal daily movement as the Euclidean distance from a location on day 1 to day 2. Breeding season (1 Apr-30 Sep) movement averaged 128 m in 2010 and 147 m in 2011. Daily movement averaged 163 m during the 2010–2011 non-breeding (1 Oct-31 Mar) season. Multiple regression analysis indicated annual food plots, disk blocks, firebreaks, and roads did not explain variation within daily movement regardless of season (R2 0.04). Individual bird/covey, precipitation, hours between locations, and average temperature also poorly explained movement variation. We used Program MARK to model the effect of season, year, mean daily movement, mean distance to annual food plots, disk blocks, firebreaks, and roads on survival. The season (breeding/non-breeding) model explained 81% of the variation in survival, and the year model explained 13%, suggesting management was not driving survival. We do not believe disking should be discontinued, although it did not influence movement, as it can improve vegetation structure important to nest-site selection and broods.

Relationship Among Plasma Tiglycerides, Body Mass, Reproduction of Northern Bobwhites

The earliest potential initiation of northern bobwhite (Colinus virginianus) reproduction is limited by photoperiod. Secondary factors such as lipid reserves, diet, and stress often limit the beginning of northern bobwhite reproduction, potentially reducing reproductive success and causing a shorter reproductive season. We measured late winter body masses and plasma triglycerides of wild northern bobwhites and subsequent reproductive timing and effort in 1997 and 1998 on the coastal prairie of Texas. Using body mass and plasma triglyceride levels as indices of body fat, we tested the hypothesis that the onset of reproduction and first clutch size was influenced by late winter lipid reserves. Northern bobwhite plasma triglycerides were higher (P < 0.001) and more variable (P = 0.019) in 1998, and nesting began 15 ± 1.6 days (c ± SE) earlier than in 1997. However, within each year, no combination of body mass and triglycerides was associated with timing of nesting or size of first clutch (P > 0.1). In addition, body masses were not correlated with plasma triglycerides (P > 0.1). Our findings suggest that individual plasma triglyceride levels and body mass are unsuitable variables for assessing within-population differences in reproductive timing. However, mean plasma triglycerides for a population may be useful for assessing differences in reproductive timing among years and locations. The relationship between triglycerides and hormones directly affecting gonadal recrudescence, such as luteinizing hormone (LH) and prolactin, is uncertain for wild northern bobwhites. Thus, future studies should assess causes and patterns of change in these hormones.

Northern Bobwhite Population Structure and Diversity in Texas and the Great Plains

Many northern bobwhite (Colinus virginianus) populations have been experiencing severe declines. This decline is of concern to wildlife biologists, landowners, and legislators due to the popularity of this species as a game bird. Previous molecular genetic analyses for populations inhabiting intact habitats in South Texas indicate the northern bobwhite population in this region is genetically diverse with low population structure. W[e] assessed whether landscape affects the population structure and diversity for northern bobwhite in Texas and the Great Plains. We extracted DNA from hunter-harvested northern bobwhites from 19 sites in South Texas from 2004 to 2010. We analyzed 7 microsatellites (Quail 5, 8, 9, 10, 11, 12, and 15). We used FST to measure genetic structure and AMOVA for genetic variation. We built 3 matrices to compare the genetic structure with the landscape. Geographic distances (km) between sample locations were ascertained using Google Earth. A matrix of barriers incorporated large water bodies and highways. We used the Biologist Ranking Information from the National Bobwhite Conservation Initiative for the third matrix to identify the number of different habitat patches a quail would need to cross from ranch to ranch. These matrices were compared to the genetic structure (pairwise FST), using Mantel tests with 10,000 permutations. We used partial Mantel tests to test the correlation of pairwise FST to combinations of distance and barriers, distance and habitat, and barriers and habitat. Overall FST was < 0.01, suggesting low levels of population differentiation and AMOVA revealed most variation was within individuals. All Mantel tests had a positive correlation with genetic differentiation; however, barriers appear to be important factors for the observed genetic patterns.

Nest-Site Characteristics of Northern Bobwhites Translocated Into Weeping Lovegrass CRP

Habitat loss and fragmentation have been considered major causes for the decline of northern bobwhite (Colinus virginianus). There are . 400,000 ha of weeping lovegrass (Eragrostis curvula) Conservation Reserve Program (CRP) fields in the Southern High Plains of Texas some of which could be modified to provide usable habitat for northern bobwhites. Timely colonization of improved CRP habitat by northern bobwhite is unlikely without transplantation, because of distance from existing populations. We radio-marked and transplanted 94 northern bobwhite into weeping lovegrass CRP and monitored nest success. We recorded high nest success in 2002 (70%) and 2003 (71%) for northern bobwhite nesting in weeping lovegrass CRP in the area studied. The composition of weeping lovegrass CRP fields available in our study area appears to be suitable nesting cover for northern bobwhite.